Is converting XLS to XLSX free?

Yes. ConvertBoy is free with no daily limit, no watermark and no sign-up.

Is there a file size limit?

No. Your own device does the work, so the only limit is your device's memory. Very large videos take longer on slower computers.

No. The conversion happens inside your browser. Your XLS files never leave your device, and nothing is kept after you close the tab.

Yes. It works in Safari on iPhone and Chrome on Android, as well as on any computer.

Convert XLS files to XLSX for free. No size limit, no sign-up, nothing uploaded.

Choose your XLS files or drop them on this page. You can add as many as you like.
XLSX is already selected. Press Convert, or Convert all for several files.
Press Download. With several files you can download them all as one ZIP.

XLS is the older Excel spreadsheet format (before 2007). XLSX is the Excel spreadsheet format.

Is converting XLS to XLSX free?: Yes. ConvertBoy is free with no daily limit, no watermark and no sign-up.
Is there a file size limit?: No. Your own device does the work, so the only limit is your device's memory. Very large videos take longer on slower computers.
Are my files uploaded anywhere?: No. The conversion happens inside your browser. Your XLS files never leave your device, and nothing is kept after you close the tab.
Does it work on a phone?: Yes. It works in Safari on iPhone and Chrome on Android, as well as on any computer.